[R] Use mapply or lapply to a nested list

[Chao Liu]

Jim and Ben,

Thank you for your help. I will play around the commands and function you
suggested.

Best,

Chao

On Tue, Dec 22, 2020 at 4:07 AM Jim Lemon <drjimlemon using gmail.com> wrote:

> Hi Chao,
> I think what you are looking for is the "rapply" function in the base
> package. Not sure that it can do exactly what you request but worth a
> look.
>
> Jim
>
> On Tue, Dec 22, 2020 at 6:36 AM Chao Liu <psychaoliu using gmail.com> wrote:
> >
> > I want to apply a sample function to a nested list (I will call this list
> > `bb`) and I also have a list of numbers (I will call this list `k`) to be
> > supplied in the sample function. I would like each of the numbers in k to
> > iterate through all the values of each list in bb. How to do this using
> > `mapply` or `lapply`?
> >
> > Here are the data:
> > k <- list(1,2,4,3) #this is the list of numbers to be supplied in the `
> > sample.int` function
> > b1 <- list(c(1,2,3),c(2,3,4),c(3,4,5),c(4,5,6)) #The first list of bb
> > b2 <- list(c(1,2),c(2,3),c(3,4),c(4,5), c(5,6)) #The second list of bb
> > bb <- list(b1,b2) #This is list bb containing b1 and b2 whose values are
> to
> > be iterated through
> > ```
> > I created this `mapply` function but it didn't get the expected outcome:
> > mapply(function(x, y) {
> >    x[sample.int(y,y, replace = TRUE)]
> > }, bb,k, SIMPLIFY = FALSE)
> > This only returns 10 output values but I would like each number of k to
> > loop through all values of the two lists in `bb` and so there should be
> > 10*2 outputs for the two lists in `bb`. I might be using `mapply` in the
> > wrong way and so I would appreciate if anyone can point me to the right
> > direction!
> >
> > Best,
> > Chao
> >
> >         [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
>

	[[alternative HTML version deleted]]